Mesocrystals are macroscopic structures formed by the assembly of nanoparticles that possess distinct surface structures and collective properties when compared to traditional crystalline materials. Various growth mechanisms and their unique features have promise as material design tools for diverse potential applications. This paper presents a straightforward method for metal–organic coordination-based mesocrystals using nickel ions and terephthalic acid. The coordinative compound between Ni2+ and terephthalic acid drives the particle-mediated growth mechanism, resulting in the mesocrystal formation through a mesoscale assembly. Subsequent carbonization converts mesocrystals to multidirectional interconnected graphite nanospheres along the macroscopic framework while preserving the original structure of the Ni-terephthalic acid mesocrystal. Comprehensive investigations demonstrate that multi-oriented edge sites and high crystallinity with larger interlayer spacing facilitate lithium ion transport and continuous intercalation. The resulting graphitic superparticle electrodes show superior rate capability (128.6 mAh g− 1 at 5 A g− 1) and stable cycle stability (0.052% of capacity decay per cycle), certifying it as an advanced anode material for lithium-ion batteries.
Brucellosis is an important and re-emerging zoonotic disease worldwide. The prevention of human infection is achieved predominantly through the control of brucellosis in agricultural animals, which in turn depends on accurate diagnosis and vaccination. However, conventional serological diagnosis of brucellosis has several limitations, and currently available vaccines for animals have several drawbacks, including the ability to cause infection in humans. Phosphoglycerate kinase (Pgk) is one of the specific proteins reactive with mouse sera in the early stage of Brucella infection, and deletion of the pgk gene in B. abortus strain 2308 resulted in extreme attenuation of this strain in vitro and in vivo. Furthermore, the B. abortus pgk mutant has been used as a live vaccine, and in challenge experiments, it induced protection that was superior to that conferred by commercial strains. In this study, the pgk gene from Brucella abortus 544 was successfully amplified and cloned into a maltose binding protein fusion protein expression vector (pMAL). The recombinant protein was expressed in Escherichia coli DH5α and purified. The immunogenicity of purified recombinant B. abortus 544 Pgk (rPgk) was evaluated by western blot analysis using Brucella-positive mouse sera. rPgk could be used as an antigenic component for future serological tests and potential vaccine development.
Brucellosis is a notorious zoonotic disease with global implications. Efforts to control the spread of the disease have been restricted to the agricultural livestock. Increasing incidences of accidental human infection have motivated researches to start working on alternative vaccines. At present, live attenuated vaccines are the only accepted type of vaccines used in developed countries for the prevention of brucellosis. Although serodiagnosis is occasionally unreliable, some countries have already claimed to have eradicated the disease, based on this testing. Live attenuated vaccines are not suitable for use in pregnant and immune-depressed animals. Moreover, these vaccines are not tolerated in humans. Therefore, many researches have been striving to discover alternative methods of vaccination. Most research has focused on the generation of subcellular, subunit, and DNA vaccines that are as efficient as the live attenuated vaccines. At present, none of the available vaccines has been able to replace the live attenuated vaccines. Therefore, additional research is necessary in order to discover a new brucellosis vaccine that is suitable for human use.
Brucellosis is an important bacterial zoonotic infection worldwide responsible for economic losses in livestock industries which represents a considerable and increasing public health burden. The disease is caused by Brucella which possess the ability to invade and replicate within phagocytes and may result to chronic infection, leading to difficulty in medical therapy of the disease. The treatment for brucellosis employs conventional principles that have been applied for a long time and a combination of antibiotics is currently used due to low efficacy of monotherapies. However, vital effects with respect to health and safety are neglected. Nevertheless, the preventive methods and treatments for brucellosis using traditional medicine have not yet been thoroughly studied, hence, alternative therapies such as the use of natural plant extracts as traditional medicine that are safe, efficient and economical should be explored in order to identify candidates that eliminate complications due to brucellosis. Coptis chinensis Franch (Huanglian) is a traditional Chinese medicinal herb and its extract has been known to possess strong antibacterial activity. In this study, the antibacterial effects of C. chinensis Franch extracts, and the major components of the herb namely berberine and palmatine, were investigated on B. abortus. The C. chinensis Franch ethanol extracts (CCFE) showed bactericidal effects at 1,000 μg/ml concentration and berberine at 100 μg/ml concentration. However, C. chinensis Franch and its components did not affect invasion and intracellular growth of B. abortus in RAW 264.7 cells. In conclusion, C. chinensis Franch ethanol extracts, water extract and its major components such as berberine and palmatine would be a beneficial antimicrobial agent without affecting phagocytic pathway within macrophages, and further study for the precise mechanisms of antibacterial effect would be necessary.